Utilization suitabilities of the three strains, ge (giant embryo), du (dull endosperm) and wx (glutinous endosperm) of rice (Oryza sativa L.) newly bred at National Institute of Agrobiological Resources, were investigated. SDS-PAGE of the milled rice proteins extracted into 62.5mM tris-HCl buffer (pH 6.8, 2% SDS, 5% 2-ME) was carried out by the method of LAEMMLI using 8% acrylamide gel. More than 40 clear protein bands were detected by CBB staining, but electrophoretic pattern showed marked similarity of these strains. Therefore, it seemed necessary to develop a fractionation method of proteins or other useful staining to distinguish the different strains. Giant embryo mutant bearing ge locus had remarkably large embryo, and contained as much as 3.3% of crude fat in the milled rice. After polishing by an abrasive-type milling machine, a part of the embryo remained, which is profitable from a nutritional viewpoint. By the use of a friction-type milling machine, embryo was removed perfectly, which led to milling yield of 85%. Its amylose content was rather high (21.6%), and its properties were similar to those of typical non-glutinous rice varieties in regard to puffing suitability or the cooked rice texture. Glutinous endosperm mutant bearing wx locus manifested the similar properties with the usual glutinous rice varieties. Most of starch was liquified by puffinng, wx mutant seemed suitable for a material for porriage or soup. Dull endosperm mutant bearing du locus showed intermediate processing suitabilities between glutinous and non-glutinous rice, because its amylose content was 10.9%. The rice grains of the dull strain was a little chalky, and the texture of the cooked rice was similar to those of glutinous varieties. Gelatinization temprature on amylography of the dull mutant was rather higher than usual glutinous rice, and peak viscosity was about 50% of usual non-glutinous rice. Dull mutant, then, was found to be suitable for puffing because it expanded well without any excess liquification of starch.

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The rheological features of Tororo (ground tuber of yam) are considered to be du e to viscous polysaccharide contained in it. In this study, the polysaccharide conten t was determined by gel-permeation column chromatography using a line of three columns packed with Toyopearl HW-65, HW-75, HW-40 in order. The water extract of tororo applied on the column was fractionated successfully into a peak of viscous polysaccharide separ ated from other sugars and proteins. The recovery test using the purified polysaccharide o f yam resulted in 101.1% and it was confirmed that the chromatographic procedure was u seful for determination of viscous polysaccharide in yam. On tororo prepared from thirteen kinds of varieties, this chromatographic determination of polysaccharide and also viscome tric and tensile tests for rheological properties were carried out, and the following res ults were obtained. (1) The polysaccharide content of yams examined here ranged from 126mg% of Nagaimo to 911mg% of Jinenjo. (2) The polysaccharide content was correlated with mechanical characteristics of tororo (B-viscometer and L, S and L×S values on the tensile test). Among these relationships, a correlation coefficient on L value reflectin g spinnability of tororo showed high value, 0.870. On the basis of these results, it was found that Jinenjo, KaU-02, KaU-09, KaU-14 were preferable for processing purpose.

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On application of fumaric or lactic acid in sake making, we studied aerating culture of genus Rhizopus in a liquid medium containing polished rice. The following medium for acid prbduction was established: the liquid medium consisted of 9% polished rice (polished rate of 75%), 0.1% KH₂PO₄, 0.05% MgSO₄·7H₂O, and 0.05% CaCl₂·2H₂O. After 240g of rice and 2.64l of additional minerals water in a jar fermentor (5l) was sterilized for 15min at 120°C, the culture was inoculated with Rhizopus spp. and incubated under the aeration of 4.0l/min and 1200rpm, for 4days at 30°C. The cultivation of R. javanicus TUA 055 provided acidity of 22-24ml, fumaric acid 10111-12327ppm, succinic acid 2008-2478ppm, malic acid 1193-1706ppm, α-ketogutaric acid 732-925ppm and lactic acid 133-486ppm. In the case of R. tonkinensis TUA192, acidity of 20.0ml, lactic acid 14671ppm, malic acid 124ppm, succinic acid 77ppm and citric acid 27ppm were obtained. These results were almost the same as those on shaking culture.

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For enumerating the groups of lactic acid bacteria in fermented pickles, selective effects of PES (Phenyl Ethyl Alcohol-Sucrose Agar), M-Enterococcus and M-LBS media were studied by the use of bacteria closely related to fermented pickles. It was suitable for enumeration of leuconostocs to incubate for 3 or 4 days at 20°C using the PES medium containing sucrose and phenyl ethyl alcohol due to the production of dextran and theinhibition of Gram-negative bacteria. The commercially available M-Enterococcus agar medium was applicable to enumerate streptococci and pediococci by incubation for 3 or 4days at 37°C. It was suitable for enumeration of lactobacilli to incubate for 4 days at 30°Cusing the M-LBS medium modified by addition of acetic acid and sodium acetate to thecommercially available LBS medium. Effectiveness of the enumerating media described her was confirmed by applying to examine the changes of microflora during the fermentation ofcabbage.

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To determine the plasma cholesterol-lowering component in coix (Coix lachryma-jobi L. var. ma-yuen (Roman.) Stapf), coix was separated into lipid-free residue, total lipids and the three lipid fractions: neutral lipid, glycolipids and phospholipids. The effect of these components on the plasma cholesterol levels was studied in rats. Plasma cholesterol level (P<0.05) and weight gain (P<0.01) in the rat fed on the lipid-free residue diet lowered significantly when compared with those on the control diet. However, there were no significant differences in plasma cholesterol levels between the dietary groups of coix lipid diet and the control. These results suggest that the hypocholesterolemic effect of coix is caused by the lipid-free residue fraction. Moreover, it will be possible to make foods which have the plasma cholesterol-lowering effect from defatted coix powder.

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Dehydration rates of fish flesh by expression have been measured under various conditions. Sample flesh was frozen-stored river chum (Oncorhynchus keta)* which had higher moisture contents than the same fish in ocean. Experimental results were compared with a rheological model, Voigt type 4-element-model, for deformation of visco-e lastic materials. Model constants were determined for each run with a curve fitting met hod by substituting an amount of dehydration per cross-sectional area for that of defor mation. By correlating these constants with operating variables, behavior of dehydration bu ried in large dispersion became clear as follows. Each Voigt element played an important role in both early and later stage of dehydration. Although the observed dehydration rates we re almost independent of pressure, model constants were strongly dependent on it. They wer e different in stages and pressure ranges. In early stage at higher pressure range, and in l ater stage except at transition range, characteristics of the spring and the dashpot were o bserved. And these constants were inversely proportional to the initial sample weight. As a r esult, the model was applicable to the above regions.

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The antioxdative activities of water, ethanol and diethyl ether extract obtained from 48 herbs on methyl linolenate were investigated in the comparision of BHA. The results indicated the presence of strong antioxidative substances in ethanol extracts obtained from boldo, catnip, white oak and tonka beans, in water extracts obtained from white oak and in diethylether extracts obtained from boldo, penny royal and white oak.

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Utilization of both "the cultivated liquid of lactic acid producing Rhizopus tonkinensis TUA 192 and fumaric acid producing R. javanicus TUA 055 were investigated as sulstitutes for lactic acid in mashing of sokuzyo-moto. The growth of putrefactive lactobacterium in sokuzyo-moto within pH value of 3.84-4.02 was completely inhibited with the addition of "the cultivated liquid of R. spp." of 0.2-0.26l in 0.8l of mash. Growth of putrefactive lactobacterium was inhibited in moromi in a similar manner as in sokuzyo-moto using lactic acid. A little difference was observed in the organic acid composition of the filtrates of moromi prepaved with "the cultivated liquid of R. spp." and with lactica cied. However he change in flavor was indistinguishable between them.

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A dehydrating device called contact-dehydrating sheet, is known to have an excellent capacity in dehydrating foodstuffs when it comes in contact with them. The effect of the sheet treatment on the color of bigeye tuna muscle was studied. Samples of 1.5cm thick were dehydrated by covering the sample slab with the sheet on the top side. After dehydrating for 5, 12h, 1, 2, 3 and 5 days at 3°C, each of the sample slabs wassliced horizontally along the treated side into 3 layers of equal thickness. It was found that the distribution of water removal in tuna muscle was more uniform than what occurred in beef and this uniformity might be due to less adipose and connective tissues. The ratio of metmyoglobin formation inupperlayerof dehydrated sample was the same with that of control and gradually increased with the prolonged treatment time. The iron content of samples rose from about 0.8 to 1.1mg% during the 5-day period dehydration. However, there was not much difference in redness of bigeye tuna muscle with the controls at varied iron content in this range. This phenomenon was thought to be due to the particular pattern of color (Mb) change in bigeye tuna muscle. This pattern was not significantly influenced by the formation of metmyoglobin.

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